In opposing a referendum on the new European Union treaty, ministers argue that in a parliamentary democracy it is right and proper that parliament should decide.

There are valid arguments about the differing merits of direct and representative parliamentary democracy; but there are three basic reasons why the official line won’t wash.

First, when the government promised a referendum on the EU constitution there was, rightly, no perceived conflict with representative parliamentary democracy. On the contrary, it was part of the case that Labour candidates took to the country in the 2005 general election. Now ministers want to renege on the grounds that the “constitutional approach” has been dropped or that the new treaty, unlike the EU constitution, is simply amending previous treaties. This puts form above content and is tendentious.

The original version of the constitutional treaty was also an “amending treaty”, in the sense that both the original and the new version take over the text of the existing treaties but add lots of new content as well. The substance has remained the same. It has just been made more difficult to understand.

As Valéry Giscard d’Estaing, the leading author of the constitution, said: “All the earlier proposals will be in the new text, but will be hidden and disguised in some way.”

All the important changes in the constitution remain: the introduction of majority voting in many new areas and the reduction of member states’ ability to block legislation when majority votes are taken; the new powers of the Court of Justice in criminal justice and policing; and the new institutions such as the council president.

Only Britain is pretending that this new treaty is a different animal from the defeated constitution; and even here ministers have implicitly conceded, falling back on the argument that we have secured opt-outs and defended red lines.

However, these are vulnerable and are also broadly the same as were negotiated last time when a referendum was promised. No let-out for the government there.

Secondly, we should be realistic about parliamentary democracy. Over centuries of British history there have been struggles to control an overmighty executive. It is important not to be naive about these things: there was no “golden age” when MPs debated matters independently of faction.

Today the executive’s dominance (of the Commons in particular) is entrenched. The government’s majority is huge, the payroll vote and other placements are large and growing. In any case the new EU treaty cannot be amended so the whole purpose of debate and argument, let alone “line by line scrutiny”, is nullified.

The inability of the Commons to scrutinise this treaty is part of a wider malaise. Westminster has largely failed to hold ministers accountable to agreements made in Brussels. Parliamentary committees are informed but only after the decisions have been taken. Much implementation is by statutory instruments, which cannot be amended. In this context, to uphold parliamentary democracy as a reason for not having a referendum raises cynicism to new levels.

The third factor undermining the case for leaving the decision to parliament is the nature and content of the new EU treaty. National parliaments are instructed “that they shall contribute actively to the good functioning of the Union”. It is central to Britain’s constitution that parliament cannot bind its successors; yet that’s what this obligation in the new treaty is proposing. This might conflict with Britain’s national interests.

The repeated assertion by the government that this treaty strengthens national parliaments is wrong. There is a mechanism whereby the European commission has to justify a proposal, but this is a charade.

In the unlikely event that a third of national parliaments, in nine countries, all vote against a proposal within an eight-week period then the commission has to “reconsider” the proposal – but having done so it can still ignore national parliaments.

The new treaty introduces provisions of the rejected constitution that allow EU leaders to change treaties incrementally without the need for more new treaties. Such agreements have to be ratified by each country in line with its own constitutional requirements (a bill or a statutory instrument in the UK), but since no new treaty is required integration can proceed by stealth.

Beyond that, the new treaty allows EU leaders to move to majority voting in any of the remaining areas covered by unanimity (including foreign policy, but excluding defence) and such changes do not need to be ratified by parliaments. Any proposal goes through unless a national parliament objects within six months: but this requires a government allowing parliament time to vote against something to which it has already agreed.

In practice this is the last opportunity for a referendum. The notion that a decision on this treaty should be by parliament rather than by referendum is like telling someone to trust a court when the jury is rigged.

The government should stick to Labour’s manifesto promise on a referendum and it should be reaffirmed in any future manifesto for a “snap” election. To do otherwise would either break a commitment to the electorate or be based on a deception: the notion that the new treaty is in any meaningful way different from the previous constitution. Neither course is likely to help Labour’s cause or build trust with the people.

Gisela Stuart is Labour MP for Birmingham, Edgbaston

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